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F.A.Q.
:
Does Indoor Tanning Produce Vitamin D?
For years Dr. Michael
Holick, director of the General Clinical Research Center at
the Boston University School of Medicine, has talked about
the theory of "Vitamin D Winter" - a term he coined
describing the fact that there is not sufficient UVB
outdoors from November through March in the Northeast for a
person to even produce vitamin D. This may explain why so
much of the population is vitamin D deficient.
Dr. Holick's
work in the mid 1990s showed that there is no reliable
source of vitamin D in our diets, that vitamin D levels
reported on milk cartons are overestimated half of the time
and that 15-20 percent of milk has no vitamin D content at
all. That leaves sun exposure and vitamin supplementation as
the only alternatives. Since it is not reasonable to assume
that the entire population will turn to vitamin
supplementation, that puts sunshine back into play as an
important source of this important vitamin. "With adequate
exposure to sunlight, dietary vitamin D becomes unnecessary,
according to Holick in an article he wrote in The
Lancet, " It is remarkable how exposure to sunlight a
few times a week can reduce the risk of osteoporosis,
osteomalacia, muscle weakness, fractures and maybe some of
the common cancers, but also induce a sense of well-being."
Sunlight is proving to
be the most reliable source of vitamin D, but does a tanning
unit provide the same benefit? In 1998, Holick published a
paper in the medical journal The Lancet showing that 41
percent of hospital patients at Massachusetts General
Hospital were vitamin D deficient. Since that time, with
funding from ITA (International Tanning Association) and The
International Smart Tan Network, Holick has compiled data on
another group of chronically unexposed people: his own
medical students, whose studies leave them little time
outdoors at all. "These are people who never see the light
of day," Holick explained. Sure enough, 41 percent of his
medical students were vitamin D deficient. But, upon
exposure to the tanning beds in Holick's lab, the condition
was corrected. Holick plans to publish a paper on this data
in the near future. "It will show that indoor tanning is a
very effective way to maintain your vitamin D status,"
Holick said.
Dr. Holick also
believes there may be a link between melanin production and
vitamin D production. Using a flash spectrometer Holick was
able to "measure" and chart the progress of the medical
students' tans. Two hours after tanning, the group showed
immediate pigment darkening - a 2-3 percent increase in
pigmentation. Within 48 hours, melanin content increased up
to 40 percent. Holick believes This data will help him
explore that theory.
Dr. Holick's new book
"The UV Advantage" is based on 30 years of research. It will
change the way people look at UV light and tanning.
Purchase
The UV Advantage
(hardcover), on sale now.
Copyright
©
2008 Ray Allard
All Rights Reserved
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Tanning
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